condition mean min max ZT0-3 4.346550000000001 4.346550000000001 4.346550000000001 ZT4-7 3.7545200000000003 3.7545200000000003 3.7545200000000003 ZT8-11 3.777045 3.777045 3.777045 ZT12-15 3.18261 3.18261 3.18261 ZT16-19 4.9382649999999995 4.9382649999999995 4.9382649999999995 ZT20-23 3.463485 3.463485 3.463485